Segment Information - Information About Reported Segments (Details)	3 Months Ended
	Mar. 31, 2018 USD ($) Segments	Mar. 31, 2017 USD ($)
Segment Reporting Information [Line Items]
Racing	$ 23,700,000	$ 23,900,000
TwinSpires	63,200,000	52,000,000
Casino	98,100,000	87,500,000
Other Investments	4,300,000	4,100,000
Adjusted EBITDA	$ 49,200,000	36,300,000
Number of Operating Segments | Segments	5
Property, Plant and Equipment, Additions	$ 34,000,000	37,500,000
Intercompany net revenues	0	0
Comprehensive income	182,000,000	7,200,000
Foreign currency translation, net of tax	0	100,000
Net income	182,000,000	7,300,000
Income (Loss) from Discontinued Operations, Net of Tax, Attributable to Parent	(167,900,000)	(5,100,000)
Income (Loss) from Continuing Operations, Net of Tax, Attributable to Parent	14,100,000	2,200,000
Depreciation and amortization	13,800,000	24,500,000
Income tax (provision) benefit	2,600,000	600,000
Stock-based compensation	6,100,000	4,900,000
Transaction expense, net	1,400,000	0
Calder exit costs	0	400,000
Total adjustments to EBITDA	9,100,000	7,500,000
Adjusted EBITDA	49,200,000	36,300,000
Racing Segment [Member]
Segment Reporting Information [Line Items]
Racing	23,700,000	23,900,000
Adjusted EBITDA	(9,400,000)	(9,700,000)
Property, Plant and Equipment, Additions	23,000,000	23,600,000
Intercompany net revenues	2,500,000	2,200,000
Racing Segment [Member] | Churchill Downs
Segment Reporting Information [Line Items]
Racing	2,000,000	2,300,000
Intercompany net revenues	300,000	300,000
Racing Segment [Member] | Arlington Park
Segment Reporting Information [Line Items]
Racing	8,300,000	8,500,000
Intercompany net revenues	1,200,000	1,000,000
Racing Segment [Member] | Fair Grounds
Segment Reporting Information [Line Items]
Racing	12,800,000	12,500,000
Intercompany net revenues	1,000,000	900,000
Racing Segment [Member] | Calder
Segment Reporting Information [Line Items]
Racing	600,000	600,000
Casino Segment [Member]
Segment Reporting Information [Line Items]
Casino	98,100,000	87,500,000
Adjusted EBITDA	44,300,000	35,300,000
Property, Plant and Equipment, Additions	3,400,000	8,100,000
Casino Segment [Member] | Oxford Casino
Segment Reporting Information [Line Items]
Casino	24,200,000	20,900,000
Casino Segment [Member] | Riverwalk Casino
Segment Reporting Information [Line Items]
Casino	14,400,000	11,500,000
Casino Segment [Member] | Harlows Casino
Segment Reporting Information [Line Items]
Casino	13,300,000	13,500,000
Casino Segment [Member] | Calder Casinos
Segment Reporting Information [Line Items]
Casino	24,300,000	21,400,000
Casino Segment [Member] | Fair Grounds Slots
Segment Reporting Information [Line Items]
Casino	10,600,000	10,200,000
Casino Segment [Member] | VSI
Segment Reporting Information [Line Items]
Casino	11,000,000	9,700,000
Casino Segment [Member] | Saratoga Casino Holdings, LLC [Member]
Segment Reporting Information [Line Items]
Casino	300,000	300,000
TwinSpires [Member]
Segment Reporting Information [Line Items]
TwinSpires	63,200,000	52,000,000
Adjusted EBITDA	16,500,000	13,200,000
Property, Plant and Equipment, Additions	2,300,000	3,200,000
Intercompany net revenues	400,000	300,000
Other Investments Segment [Member]
Segment Reporting Information [Line Items]
Other Investments	4,300,000	4,100,000
Property, Plant and Equipment, Additions	4,600,000	400,000
Intercompany net revenues	1,200,000	1,400,000
Corporate
Segment Reporting Information [Line Items]
Adjusted EBITDA	(2,500,000)	(3,100,000)
Property, Plant and Equipment, Additions	700,000	200,000
Intersegment Eliminations [Member]
Segment Reporting Information [Line Items]
Intercompany net revenues	(4,100,000)	(3,900,000)
Saratoga Harness Racing Inc Joint Venture [Member]
Segment Reporting Information [Line Items]
Adjusted Corporate EBITDA	(2,500,000.0)	(3,100,000.0)
Saratoga Harness Racing Inc Joint Venture [Member] | Racing Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	(9,400,000.0)	(9,700,000.0)
Saratoga Harness Racing Inc Joint Venture [Member] | Casino Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	44,300,000.0	35,300,000.0
Saratoga Harness Racing Inc Joint Venture [Member] | TwinSpires [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	16,500,000.0	13,200,000.0
Saratoga Harness Racing Inc Joint Venture [Member] | Other Investments Segment [Member]
Segment Reporting Information [Line Items]
Adjusted EBITDA	300,000.0	600,000.0
Continuing Operations [Member]
Segment Reporting Information [Line Items]
Depreciation and amortization	13,800,000	14,200,000
Interest expense	9,600,000	11,800,000
Income tax (provision) benefit	2,600,000	600,000
Earnings Before Interest Taxes Depreciation and Amortization	40,100,000	28,800,000
Stock-based compensation	2,800,000	3,400,000
Pre-Opening Costs	600,000	0
Other income, expense:	0	(200,000)
Interest, depreciation and amortization expense related to equity investments	4,300,000	3,500,000
Transaction expense, net	1,400,000	0
Calder exit costs	$ 0	$ 400,000